<!DOCTYPE html>
<html lang="en">
<link rel="stylesheet" href="../../js/chosen/chosen.css">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>

<select class="chosen-select" multiple style="width: 500px;">
    <option value=""></option>
    <option value="1">American Black Bear</option>
    <option value="2">Asiatic Black Bear</option>
    <option value="3">Brown Bear</option>
    <option value="4">Giant Panda</option>
    <option value="5">Sloth Bear</option>
    <option value="6">Sun Bear</option>
    <option value="7">Polar Bear dd</option>
    <option value="8">Spectacled Bear</option>
</select>

<button id="btn1">按钮</button>

<script src="../../js/jq/jquery-1.8.3.min.js"></script>
<script src="../../js/chosen/chosen.jquery.js"></script>
<script>
    $(".chosen-select").chosen({});
    $("#btn1").click(function () {
        console.log($(".chosen-select").val());
    });
</script>
</body>
</html>